Prevent Firefox from spamming errors

static/scripts/inputs.mjs

@@ -142,7 +142,7 @@ export class MIDI extends Input{
 			// Turn off keyboard mode
 			output.send([0xB0, 0x00, 0x00])
 
-			// MIDI only supports 7-bit values, so we have to divide ditduration by two
+			// MIDI only supports 7-bit values, so we have to divide dit duration by two
 			output.send([0xB0, 0x01, this.ditDuration/2])
 
 			// Send keyer mode

static/scripts/outputs.mjs

@@ -357,7 +357,7 @@ class MIDIBuzzer extends Buzzer {
 		let ms = when?when - Date.now():0
 		setTimeout(
 			() => {
-				for (let output of this.outputs) {
+				for (let output of (this.outputs || [])) {
 					output.send(message)
 				}
 			},